Adding External Scsi Drives; Scsi Cable Length Guidelines - Intergraph InterServe 80 SL System Reference Manual

8. Install the two screws that secure the drive bracket assembly front mounting tabs to the
chassis.
9. Install the screw that secures the drive bracket assembly to the right side of the chassis.
10. Install the right cover.
11. Connect the SCSI cable and the power cable to the new drive.

Adding External SCSI Drives

You can add single-ended external SCSI drives to the system by connecting them to the
Ultra SCSI port on the back of the system. A Wide Ultra SCSI external port is optional with
a SCSI controller card. See "External Ports" in Chapter 5, for an illustration of port
locations.
You can also install additional SCSI expansion cards (adapters) to support external SCSI
drives. See "Adding Option Cards" for details.
NOTE Most SCSI adapters do not recognize a hard disk drive that was formatted using a different
brand of adapter. For example, a hard disk drive formatted with an Adaptec SCSI adapter
will not work with a Symbios SCSI adapter. You must use only Symbios-formatted hard disk
drives with a Symbios SCSI adapter.

SCSI Cable Length Guidelines

The number of drives and length of the cables used to connect the drives is a factor when
using SCSI-1, Fast SCSI (SCSI-2), Ultra SCSI, and Wide Ultra SCSI drives. Fast SCSI,
Ultra SCSI, and Wide Ultra SCSI impose shorter cable restrictions than SCSI-1. The total
length of the SCSI cabling must not exceed the following:
Drives
One to Four
Five to Seven
NOTE The SCSI controller (on the system board or an adapter card) counts as one device.
The total length of the SCSI cabling is the sum of the following:
u
Wide Ultra SCSI cable inside the system - 52 inches (132 cm)
u
Ultra SCSI cable inside the system - 14 inches (35.5 cm)
u
SCSI cable inside each device - typically 8 inches (20 cm)
SCSI-1 Fast SCSI-2
19.8 ft 9.9 ft
(6 meters) (3 meters)
9.9 ft 9.9 ft
(3 meters) (3 meters)
Ultra SCSI Wide Ultra SCSI
9.9 ft 9.9 ft
(3 meters) (3 meters)
4.5 ft 4.5 ft
(1.5 meters) (1.5 meters)
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